SAN DIEGO–Caltrans crews will close two freeways this week for construction work. Early Wednesday, crews closed all lanes of northbound Interstate 805 (I-805) at the northbound Interstate 5 (I-5)/I-805 split in Sorrento Valley from 12:01 am to 4 a.m. to install a new sign structure. The structure includes self-reflective signs that use headlights from vehicles on the highway to illuminate the signs. All motorists will be detoured to the northbound I-5/State Route 56 local Bypass Lane. On Wednesday and Thursday night, all lanes of State Route 163 (SR-163) between Interstate 8 (I-8) and Genesee Avenue will close from 11 p.m. to 5 a.m. so crews can continue installing falsework on the Friars Road Bridge. The northbound lanes will close on Wednesday night and the southbound lanes will close Thursday night. At no time will SR-163 close in both directions at the same time. During the SR-163 full freeway closures, crews will begin closing some of the freeway lanes at 7 p.m., with all lanes closing by 11 p.m. The closure also includes the eastbound and westbound I-8 connector ramps to northbound SR-163. In addition, the eastbound Friars Road on-ramp to northbound SR-163 will be closed. The Genesee Avenue on-ramp to northbound SR-163 will remain open. All southbound SR-163 motorists will be detoured to southbound I-805 to westbound I-8 to the southbound SR-163 connector ramp. All northbound SR-163 motorists will be detoured to eastbound I-8 to northbound I-805 to the merge at northbound SR-163. Traffic controls and detour signs will be placed to alert motorists in advance. Crews will take the opportunity to clear trash from the area. Caltrans reminds drivers to ‘Be Work Zone Alert’ by avoiding distracted driving, paying constant attention to traffic, and slowing down when approaching work zones.